Presetting device for electronic musical instrument

ABSTRACT

A device for memorizing and reproducing a position of a continuously adjustable controller, comprising a rotatable yoke of magnetic material and adapted to rotate on a pivot axis to the position corresponding to the position of adjustment of said adjustable controller, an armature rotatably mounted on said pivot axis in close proximity to said rotatable yoke and having a coil thereon and a brake adapted to brake the rotation of said armature, whereby the position of the adjustable controller can be memorized by releasing the brake from the armature and then energizing the armature coil to rotate the armature to the position of said rotatable yoke and the position of the controller can be reproduced by applying the brake to the armature and energizing the armature coil to rotate the rotatable yoke to tee position of the armature.

United States Patent Suzuki July 4, 1972 [54] PRESETTING DEVICE FOR [56]References Cited ELECTRONIC MUSICAL INSTRUMENT UNITED STATES PATENTS[72] Inventor: Nobuhilto Suzuki, Hamamatsu, Japan 554,080 2/1896 McElroy335/149 l,702,988 2/l929 Wright [731 Ass'gnw "WW" sell" Keb'lflllkh2,6l5,945 10/1952 13mm v.317/123 matsu-shi, Japan [22] Filed: Sept. 22,1970 Primary Examiner-Harold Broome Appl. No.: 74,475

Related U.S. Application Data Continuation of Ser. No. 76l,034, Sept.20, 1968.

Foreign Application Priority Data 335/254, 266, 267, 73, 74, I77, l82,I84, I49

Attorney-Stevens, Davis, Miller 81 Mosher [57] ABSTRACT A device formemorizing and reproducing a position of a continuously adjustablecontroller, comprising a rotatable yoke of magnetic material and adaptedto rotate on a pivot axis to the position corresponding to the positionof adjustment of said adjustable controller, an armature rotatablymounted on said pivot axis in close proximity to said rotatable yoke andhaving a coil thereon and a brake adapted to brake the rotation of saidarmature, whereby the position of the adjustable controller can bememorized by releasing the brake from the armature and then energizingthe armature coil to rotate the armature to the position of saidrotatable yoke and the position of the controller can be reproduced byapplying the brake to the armature and energizing the annature coil torotate the rotatable yoke to tee position of the armature.

13 Claims, 16 Drawing Figures Patented July 4, 1972 5 Sheets-Sheet l I II I I I I I I I I FIG. 2

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ATTORNEYS PRESE'I'IING DEVICE FOR ELECTRONIC MUSICAL INSTRUMENT Thisapplication is a continuation of Ser. No. 161,034 filed Sept. 20, 1968.

More specifically, it relates to a device for memorin'ng and reproducinga combination of positions of a plurality of adjustable conu'ollers.Although the invention can be advantageously applied to a presettingdevice for an electronic musical instrument which can memorize andreproduce positions of operating means of continuously adjustablecontrollers for controlling tone colors, coupler tones, degrees ofmusical effects or the like of the electronic musical instrument, theinvention is not limited to such use but may find more broadapplication.

It is an object of the present invention to provide a device which canvery easily memorize and reproduce a position of a continuouslyadjustable controller with a very simple mechanism which can bemanufactured at low cost.

It is another object of the present invention to provide a device of theabove character which produces no noise during operation.

It is another object of the present invention to provide a device whichcan very easily memorize and reproduce any combination of positions ofoperating means of a plurality of continuously adjustable controllers.

In accordance with an aspect of the present invention there is provideda device for memorin'ng and reproducing a position of adjustment of acontinuously adjustable controller, comprising a rotatable yoke of softmagnetic material, for example soft iron, and adapted to rotate on apivot axis to the position corresponding to the position of adjustmentof said adjustable controller, an armature rotatably mounted on saidpivot axis in close proximity to said rotatable yoke and having a coilthereon, and a brake adapted to brake the rotation of said armature,whereby the position of the adjustable controller can be memorized byreleasing the brake from the armature and energizing the coil of saidarmature to rotate the armature to the position of said rotatable yokeand the position of the adjustable controller can be reproduced byapplya ing the brake to the armature and energizing the coil of saidarmature to rotate the rotatable yoke to the position of the armature.

In accordance with another aspect of the present invention there isprovided a device for memorizing and reproducing positions of adjustmentof continuously adjustable controllers, comprising rotatable yokes ofsoil magnetic material each associated with each of said adjustablecontrollers and adapted to rotate on a pivot axis to the positioncorresponding to the position of adjustment of said adjustablecontroller, armatures rotatably mounted on said pivot axis in closeproximity to said rotatable yoke and having a coil thereon, and a brakeadapted to brake the rotation of the armature, whereby the position ofany of the adjustable controllers can be memorized by releasing thebrake from the corresponding armature and energizing the coil thereof torotate said armature to the position of the rotatable yoke and can bereproduced by applying the brake to said armature and energizing thecoil to rotate the rotatable yoke to the position of the armature.

Now the present invention will be explained with reference to thedrawings which illustrate the embodiments of the present invention whichare embodied in a presetting device for an electronic musicalinstrument. It will be understood, however, that the invention can becarried out in the form other than the presetting device of theelectronic musical instrument.

In the drawings:

FIG. 1 is a side view of a first embodiment of the invention;

FIG. 2 is a sectional view taken along line Il-II in FIG. 1;

FIG. 3 is an electric circuit diagram of a presetting system using thedevices as shown in FIG. 1;

FIG. 4 is a side view of a second embodiment of the invention;

FIG. 5 is an electric circuit diagram of a presetting system using thedevices as shown in FIG. 4;

FIG. 6 is a side view ofa third embodiment of the invention; FIG. 7 is asectional view taken along line VII-VII in FIG.

FIG. 8 is a sectional view taken along line VIII-VIII in FIG.

FIG. 9 is a sectional view taken along line IX-IX in FIG. 8;

FIG. [0 is an electric circuit diagram of a presetting systemusingthedevioesmshown in-FIG. 6-,

FIG. 11 is a sectional view similar to FIG. 8 showing a fourthembodiment of the present invention;

FIG. 12 is a sectional view taken along line XII-XII in FIG. I 1;

FIG. 13 is a sectional view taken along line XIII-XIII in FIG. ll;

FIG. 14 is an electric circuit diagram of a presetting system usingthedevicesasshown in FIG. 11;

FIG. 15 is a sectional view similar to FIG. 8 showing a fifth embodimentof die invention; and

FIG. 16 is a sectional view taken along line XVI-XVI in FIG. 15.

Referring to FIGS. 1 and 2 which show the first embodiment, 1 is a panelof an electronic musical instrument, 2 are continuously adjustablecontrollers, i.e. variable resistors, which are arranged on said panelin juxtaposed relationship, 3 is an operating lever of said controller,4 is a resistance element, 5 is a slide contact, and 6 is a pivot axison which the continuously adjustable controller is pivotally mounted.The

tones, couplers, musical effects such as vibrato, tremolo and.

the like of the electronic musical instrument can be controlled byadjusting the operating lever 3 of the controller 2. A rotatable yoke 7of soft magnetic material is fixed to or integral with the operatinglever 3 and armatures 8 are rotatably mounted on the pivot axis 6. Eacharmature 8 has coil 9 thereon and a brake 10 is associated therewith tobrake the rotation of the armature. The brake 10 comprises a brakingelement 12 made of an iron piece which is supported by a leaf spring 11and resiliently urged against a projection 13 formed on the centralportion of the armature. Cooperating teeth are formed on the confrontingsurfaces of the braking element 12 and the projection 13, and anelectromagnet 14 is disposed behind the braking element. The brakingelement 12 is normally urged against the projection 13 of the armatureby the leaf spring II to brake the armature, and when the electromagnet14 is energized the braking element is attracted toward theelectromagnet, thereby releasing the brake from the armature 8. Theelectromagnet I4 is supported by a plate 15.

FIG. 3 shows an electric diagram of the presetting device according tothe present invention, which includes a plurality ofcontrollers TVR,,TVR, ;coils L L,,, L, L L onthearrnaturesofthecontrollersTVR,,TVR,.release coils l 1 1 I l 1,, on electromagnets for releasing the brakingelements of the controllers TVR,, 'I'VR a push button switch MB which isadapted to be operated at the time of memorizing; and push buttonswitches C8,, C8,, CB, which are adapted to be operated at the time ofboth memorizing and reproducing.

In operation, the operating levers of the controllers TVR,, TVR, areadjusted to the desired positions, respectively, and the rotatable yokesare moved to the corresponding positions. Now the push button switch MBis operated and, with the switch MB being kept operated, one of the pushbutton switches CB C8,, CB, is operated. Asuming that the switch CB, isoperated, electric current passes through the first series of the coils1 l of the controllers TVR,, TVR, respectively to attract the brakingelements 12 (FIG. 1) to release the brakes from the armatures. At therespectively same time electric current passes through the first seriesofthe coils L L ofthecontrollersTVR TVR, to form magnetic paths throughthe arrnatures B and the rotatable yokes 7, thereby rotating thearmatures 8 of the first series to the positions of the rotatable yokes7, which are held stationary due to frictional resistance existing atthe slide contact 5 and the other parts. When the push button switchesare released, the braking elements of the brakes are again urged againstthe respective armatures to brake the rotation thereof. Thus acombination of the positions of the controllers are memorized by thefirst series of the armatures of the controllers. Other combinations ofthe positions of the controllers can be memorized by the second, thirdseries of the armatures in the same manner. When it is desired toreproduce the positions memorized by the first series of the armatures,the push button switch CB is operated, without operating the push buttonswitch MB. Then, electric current passes through the coils n nAccordingly the armatures 8 are positively held stationary by the brakesII] while the rotatable yoke 7 are rotated to the positions of thearmatures 8, respectively, against the frictional resistance, so thatthe operating levers of the controllers TVR,, TVR, are moved to thememorized positions. Thus, the positions of the controllers memorized bythe first series of the armatures are reproduced. In the same manner thepositions memorized by the second, third series of the armatures can bereproduced.

FIG. 4 shows a second embodiment of the invention, which issubstantially similar to the first embodiment. In FIG. 4, the same partsas those shown in FIG. 1 are designated by the same numerals as in FIG.I. This embodiment employs a braking element 22 made of a permanentmagnet which is resiliently urged against a projection 23 formed on thecentral portion of the arrnatures 8, by means of a spring 21. Theprojection 23 has a release coil 24 thereon. At the time of memorizing,electric current is passed through said release coil 24 in one directionto produce at the end of said projec tion 23 a magnetic pole of samepolarity as that of the confronting surface of the braking element 22 torepulse said element, thereby releasing the brake from the armature. Atthe time of reproducing, electric current is passed through said coil 24in the opposite direction to produce at the end of said projection 23 amagnetic pole of opposite polarity to that appearing at the surface ofthe element 22 to attract the permanent magnetic element, therebyapplying the brake on the armature.

FIG. 5 shows an electric circuit diagram of the presetting deviceaccording to the second embodiment, which includes a switch MB adaptedto reverse the direction of the electric current, passing through thecircuit. At the time of memorizing, the switch MB is operated to reversethe direction of the electric current and then one of the switches C8,,C8,, CB, is operated. Now assuming that the switch CI? is operated,electric current passes through the first series of the armature coils LL and the release coils 1 1 ofthe controllers TVR,, TVR producing at theend of the projections 23 (FIG. 4) a magnetic pole having the samepolarity as that of the confronting surfaces of the braking elements 22,thus repulsing the braking elements so as to allow the free rotation ofthe armatures. Then the magnetic circuits produced by the electriccurrent passing through the coils L,,, L act to rotate the armatures 8to the position of the rotatable yokes 7. By releasing the switches, theprojections 23 of the arrnatures are demagnetized and, consequently, thebraking elements 22 are urged against the corresponding projections 23,so that the arrnatures 8 are fixed or memorized. When it is desired toreproduce the memorized positions, any of the switches C8,, CB isoperated, without operating the switch MB. Asuming that the switch CB,is operated, electric current passes through the coils in the oppositedirection and produces at the end of the projections 23 (FIG. 4) amagnetic pole having the opposite polarity to that of the confrontingsurfaces of the braking elements made of permanent magnet 22.Accordingly the braking elements are more strongly urged against theprojections of the annatures, which are prevented from rotating aboutthe pivot axis, so that the rotatable yoltes are rotated to the positionof the arr-natures and the operating levers of the controller are movedto the memorized positions, respectively,

FIGS. 6 through 9 show a third embodiment of the present invention andFIG. 10 shows an electric circuit diagram. In

. but does not pass through the coils I 1,,

this embodiment each of continuously adjustable controllers is formed asa variable resistor having a click-stop. In the drawings, 31 is anoperating lever, 32 is a slide contact, 33 is a supporting arm of theslide contact, 34 is a resistance element and 35 is a click-stop made ofcorrugated spring plate. A pivot shaft 36 of the operating lever 31 hasa bevel gear 37, which meshes with a bevel gear 38 fixed on an end of arotary shah 39, on which a rotatable yoke 40 of magnetic material isfixed and armatures 4! are rotatably mounted. Each of the armatures hascoils 42 thereon and a brake 43 is associated with each armature. Thebrake 43 comprises a leaf spring 44, and a movable element 45 made of apermanent magnet resiliently urged toward the armature by said leafspring, said element 45 having a laterally projecting pin 46 which isadapted to engage with teeth formed at the marginal edge of a brakingplate 47 fixed on the side of the central portion of the armature tobrake the rotation of the armature. When memoriang, electric current ispassed through two arrnatures disposed at the opposite sides of therotary shafl 39, in the opposite directions, thereby forming magneticcircuits as shown by dash-and-dot lines 48 in FIG. 8, which produce amagnetic pole at the central portion of the armature. The magnetic poleacts to repulse the permanent magnet 45 away from the armature, thusdisengaging the pin 46 from the teeth of the braking plate 47 to allowthe free rotation of the armature. The magnetic circuits also act torotate the armature to the position of the rotatable yoke 40. When thecoil is deenergized, the pin 46 of the braking element engages thebraking plate 47 to fix the armature in this position. When it isdesired to reproduce the memorized position, electrical current ispassed throughout the armature in one direction to produce a magneticcircuit as shown by a broken line 49 in FIG. 8. No magnetic pole appearsat the central portion of the armature so that the brake is notreleased. The magnetic circuit thus fon'ned acts to rotate the rotatableyoke 40 to the position of the armature 41. The rotation of therotatable yoke is transmitted through the rotary shaft 39, bevel gears38 and 37, pivot shaft 36 to the variable resistor, which is moved tothe memorized position.

The embodiment shown in FIGS. 6 through 9 also includes a click-stopreleasing device to reduce the necessary torque for rotating therotatable yoke 40. The click-stop releasing device comprises a movablebase plate 50 on which are supported the click-stop 35 and theresistance element 34, and an electromagnet 51 which is adapted toattract said base plate downward. At the time of reproducing, thearmature coils 42 are energized and simultaneously the magnet 51 isenergized to move the base plate downward, thus moving the clickstop 35away from engagement with a detent 52 supported below the rotarysupporting arm. The detent 52 resiliently biased downward by the springsupport but does not follow the downward movement of the click-stop 35since a stopper 53 restricts the downward movement of the detent 52.Accordingly, the operating lever 31 is relieved of the resistance owingto the click-stop 35 and it can lightly rotate. Thus, the rotatable yoke40 can freely rotate at the time of reproducing.

In such a construction the resistance element 34 is also lowered by thedownward movement of the base plate 50, so that the resistance elementtends to move out of contact with the slide contact 32. In order to holdthe slide contact 32 in contact with the resistance element 34, thesupporting arm 33 is constructed of two springs 33' and 33", the spring33' being weak and having larger curvature and the spring 33" beingstrong and having smaller curvature, and the contact 32 is car ried bythe weak spring 33', which is backed up by the strong spring 33 Thecontact 32 is normally urged into contact with the surface of theresistance element 34 with strong force by both springs 33' and 33", butwhen the base plate 50 is lowered the weak spring 33' flexes so as tofollow the downward movement of the base plate to hold the contact ofthe contact 32 and resistance element 34, thereby preventing the soundfrom being interrupted at the time of release of the click-stop. FIG. 10is an electric circuit diagram which includes a plurality of variableresistors TVR,, TVR, a plurality of pairs of armature coils L,,,, L,,,,L,,,, L L and L L L L L L. of the variable resistors TVR,, TVR releasecoils 1,, l, of the click-stop releasing electromagnets of the variableresistors TVR,, TVR, a push button switch MB; and push button switchesC8,, CB,, CB, At the time of memorizing, the switch MB is operated andthen the desired one of the switches C8,, C8,, CB, for example theswitch Cl? of the first series, is operated. Electric current passesthrough the pairs of the coils of the armatures L and L l and L in theopposite directions, without passing through the coil 1,, 1 formingmagnetic circuits as shown by dash-anddot lines 48 in FIG. 8. At thetime of reproducing, the switch MB is not operated and the switch CB isoperated, so that electric current passes through the coils l 1, whichenergize the click-stop releasing electromagnets to release theclick-stops and electric current also passes through the armature coilsL, and L L and L, in one direction to produce magnetic circuit as shownby broken line 49 in FIG. 8.

FIGS. ll through 13 show a fourth embodiment of the present invention,and FIG. 14 shows an electric circuit thereof. This embodiment issubstantially similar to that shown in FIGS. 6 through 9, except that anarmature cornprises symmetrically arranged four cores 60, 61, 62 and 63,and that a brake comprises a braking element 65 made of an iron piecesupported by a leaf spring 64 and a braking plate 66 projecting from theside of the central portion of the armature, said braking plate having apin 67 adapted to engage with teeth formed on said braking element,whereby the brake can be released by attracting the braking element 65toward the central portion of the armature. FIG. 14 is an electriccircuit diagram used in this embodiment, which includes a plurality ofvariable resistors TVR,, TVR, ;first, second series of four armaturecoils L,,,, L,,,, L L, and L L L,,,, L

L211, L212 L213 L214 and ab L222, 423- L214 oft-he vari' able resistorsTVR,, TVR, (L L L L being associated with core 60, L,,,, L,, L L beingassociated with core 61, L L l L being associated with core 62, L L L Lbeing associated with core 63 in FIG. 13); coils of the click-stopreleasing electromagnets l 1, ofTVR TVR,. ;apush button switch MB; andpush button switches CB CB,

When the switch MB and the switch CB are operated, electric current doesnot pass through the coils 1,, 1 but through the armature coils from thejunctions of the coils L, and L,,,, L, and L toward the opposite ends inthe opposite directions and then from the opposite ends of the coils Land L L, and toward theirjunctions in the op osite directions.Accordingly, a magnetic circuit is formed through the four cores 60, 61,62 and 63 as shown by broken line 68 in FIG. 13 so that a magnetic poleappears at the side of the central portion of the armature, which actsto attract the braking element 65 to release the brake. The armature isrotated to the position of the rotatable yoke 69 by the action of themagnetic circuit passing through the both ends of the armature, and thenfixed by the brake so as to memorize the adjusted position. When theswitch CB, is operated, without operating the switch MB in FIG. 14,electric current passes through the coils 1,, l, to actuate theclick-stop releasing device and also passes through the armature coilsL, L,,,, L and L L L L and L, in the same direction to produce amagnetic current passing throughout the annature, thereby rotating therotatable yoke 69 to the position of the armature to reproduce thememorized position. At this time no magnetic pole appears at the centralportion of the armature, so that the brake is not released.

FIGS. 15 and 16 show a fifth embodiment of the invention, which issubstantially similar to that shown in FIGS. 11 through 13, except thata brake consists of a braking element 70 of a permanent magnet supportedby a spring and is adapted to be released from the armature by therepulsive force due to the magnetic pole produced at the central portionof the armature. In this embodiment two pairs of cores 71, 72,

73 and 74 of an armature are connected together at their opposite endsby bridge members of soft magnetic material 75 and 76. At the time ofmemorizing, two magnetic circuits are formed through the core 71, thebridge member 75, the core 73 and through the core 72, the bridge member76, and the core 74. The brake is released by the action of the magneticfield appearing at the central portion of the armature, while thearmature is rotated to the position of the rotatable yoke 77 by theaction of the magnetic leak flux appearing at the bridge members 75 and76. The magnetic leak flux can be controlled by varying the crosssectional area of the bridge members 75' and 76, and consequently, theratio of the brake releasing force and the armature rotating force canbe determined by the selection of said bridge sectional area.

it will be understood from the above description that the deviceaccording to the present invention can very easily and effectivelymemorize and reproduce any position of a continuously adjustablecontroller with a very simple construction. This device produces nonoise since it employs magnetic means without mechanical contact formemorizing and reproducing purpose. By employing a plurality ofarmatures it can memorize and reproduce a plurality of positions, andthe number of positions can be increased or decreased as desired bychanging the number of armatures. When a plurality of controllers, eachincluding a plurality of armatures, are used, the device according tothe invention can memorize and reproduce a plurality of combinations ofpositions of the controllers. This device can be advantageously employedin a presetting device for an electronic musical instrument, to memorizeand reproduce positions of operating levers of continuously adjustablecontrollers for controlling tones, couplers, musical effects and thelike of the electronic musical instrument. The position of the operatinglever on a panel of the electronic musical instrument can be easilymemorized by a simple means, such as a push button switch and also,combinations of positions of the operating levers can be memorized andreproduced by simple operation of the push button switches. When thepositions of the controllers are reproduced the operating levers aremoved to their respective memorized positions, so that the operator canconfinn the ad justed positions of the controllers and, if necessary, hecan change the adjustment of position or positions by furthermanipulating the operating lever or levers.

What is claimed is:

1. Apparatus for memorizing and reproducing a position of adjustment ofa continuously adjustable controller, comprismg:

a yoke of magnetic material rotatably mounted on a pivot axis andmovable to a position in correspondence with a position ofadjustment ofsaid controller;

an armature rotatably mounted on said pivot axis and having a coildisposed thereon, said armature being magnetically engageable with saidyoke;

energizing means for selectively energizing said coil;

brake means engaging said armature to brake the rotation of saidarmature; and

releasing means for selectively releasing said brake means fromengagement with said armature;

wherein, when said releasing means engages said brake means to releasesaid brake means from engagement with said armature and said energizingmeans energizes said coil, said armature is rotated to said position incorrespondence with said position of adjustment of said controller, and

wherein, when said brake means engages said armature to brake therotation thereof and said energizing means energizes said coil, saidyoke is rotated to a position in correspondence with said armature.

2. Apparatus according to claim 1, wherein said brake means comprises amagnetizable braking element resiliently urged into engagement with thecentral portion of the armature, and said releasing means comprises anelectromagnet disposed adjacent said braking element to selectivelyattract said braking element and release said braking element fromengagement with the armature.

3. Apparatus according to claim 1, wherein said brake means comprises abraking element of permanent magnetic material resiliently urged intoengagement with the central portion of the armature, and said releasingmeans comprises a release coil supported on said armature to repulsesaid braking element and release the brake means from engagement withthe armature.

4. Apparatus according to claim I, wherein the continuously adjustablecontroller has a click-stop and further comprising a click-stopreleasing electromagnet, to release said click-stop from the controller.

5. Apparatus according to claim 1, wherein the brake means comprises abraking element of permanent magnetic material resiliently urged intoengagement with the central portion of the armature, said armaturehaving a plurality of coils disposed thereon, wherein when electriccurrent is passed in opposite directions through said coils a magneticpole is produced at the central portion of the armature to repulse saidbraking element to release said element from the armature and whenelectric current is passed in the same direction through said coils nomagnetic pole is produced at the central portion of the armature, saidbraking element being held in engagement with said armature.

6. Apparatus according to claim 1, wherein the brake means comprises amagnetizable braking element resiliently urged into engagement wiflr abraking plate fixed to the central portion of the armature, saidarmature having a plurality of coils disposed thereon, wherein whenelectric current is passed through said coils in opposite directions amagnetic field is produced at the central portion of the armature toattract said braking element from engagement with said braking plate andwhen electric current is passed through said coils in the same directionno magnetic field is produced at the central portion of the annaturewherein said braking element is held in engagement with said brakingplate.

7. Apparatus according to claim 6, in which the armature has twoadjacent pairs of opposed coils disposed thereon, wherein when electriccurrent is passed in the opposite direction through every two adjacentcoils and in the opposite directions through every two opposed coiis themagnetic field is produced at the central portion of the armature andwhen electric current is passed in the same direction through all of thecoils no magnetic field is produced at the central portion of thearmature 8. Apparatus according to claim 1 in which the armature has twoadjacent pairs of opposed coils, every two adjacent coils having coreswhich are connected together at their ends by a bridge member ofmagnetic material.

9. Apparatus for memorizing and reproducing positions of adjustment of aplurality of continuously adjustable controllers for an electronicmusical instrument, comprising:

a plurality of yokes of magnetic material, each associated with one ofsaid controllers, each rotatably mounted on a pivot axis of thecorresponding controller and movable in correspondence with a positionof adjustment of said corresponding controller;

a plurality of armatures magnetically engagable with a correspondingyoke rotatably mounted on each said pivot axis and having armature coilsdisposed thereon, said armatures forming a plurality of series ofarrnatures, each series including the armatures engagable with arespective yoke;

energizing means for selectively engaging one of said series ofarmatures;

brake means engaging each of said armatures for braking the rotationthereof; and

releasing means for releasing each of said brake means from engagementwith said annatures.

10. Apparatus according to claim 9, comprising an electric currentsupplying source, a memorizing switch and a plurality of memorizing andre roducin switches, wherein the respective controllers mclu e a plurity of armature coils and a plurality of brake releasing coils, thecorresponding ones of said armature coils being connected to said sourcethrough the memorizing switch and one of the memorizing and reproducingswitches and the corresponding ones of the break releasing switchesbeing connected to said source through one of the memorizing andreproducing switches.

ll. Apparatus according to claim 9, comprising an electric currentsupplying source, memorizing switch means to reverse the direction ofelectric current supplied from said source, and a plurality ofmemorizing and reproducing switches, wherein the respective controllersinclude a plurality of armature coils and a plurality of brake releasingcoils, corresponding ones of the armature coils and the brake releasingcoils being connected to said source through the memorizing switch meansand one of the memorizing and reproducing switches.

12. Apparatus according to claim 9, comprising an electric currentsupplying source, a memorizing switch and a plurality of memorizing andreproducing switches, wherein the respec tive controllers include aplurality of pairs of armature coils and a plurality of brake releasingcoils, corresponding pairs of the armature coils and corresponding onesof the brake releasing coils being connected to said source through thememorizing switch and one of the memorizing and reproducing switches,the junctions of the pairs of the armature coils being connected to thesource through one of the memorizing and reproducing switches.

13. Apparatus for memorizing and reproducing a position of an adjustablecontroller having operating lever means for adjusting said controller,comprising: a rotatable yoke made of magnetic material rotatable on apivot axis, means mechanically connecting said operating lever with saidrotatable yoke, an armature member rotatably mounted on said pivot axisin close proximity to said rotatable yoke, said armature member having acoil disposed thereon in magnetic cooperation with said rotatable yoke,brake means for engaging said armature member for stopping said armaturemember, and means for actuating said brake means into engagement withand deac tuating said brake means out of engagement with said armaturemember.

1. Apparatus for memorizing and reproducing a position of adjustment ofa continuously adjustable controller, comprising: a yoke of magneticmaterial rotatably mounted on a pivot axis and movable to a position incorrespondence with a position of adjustment of said controller; anarmature rotatably mounted on said pivot axis and having a coil disposedthereon, said armature being magnetically engageable with said yoke;energizing means for selectively energizing said coil; brake meansengaging said armature to brake the rotation of said armature; andreleasing means for selectively releasing said brake means fromengagement with said armature; wherein, when said releasing meansengages said brake means to release said brake means from engagementwith said armature and said energizing means energizes said coil, saidarmature is rotated to said position in correspondence with saidposition of adjustment of said controller, and wherein, when said brakemeans engages said armature to brake the rotation thereof and saidenergizing means energizes said coil, said yoke is rotated to a positionin correspondence with said armature.
 2. Apparatus according to claim 1,wherein said brake meaNs comprises a magnetizable braking elementresiliently urged into engagement with the central portion of thearmature, and said releasing means comprises an electromagnet disposedadjacent said braking element to selectively attract said brakingelement and release said braking element from engagement with thearmature.
 3. Apparatus according to claim 1, wherein said brake meanscomprises a braking element of permanent magnetic material resilientlyurged into engagement with the central portion of the armature, and saidreleasing means comprises a release coil supported on said armature torepulse said braking element and release the brake means from engagementwith the armature.
 4. Apparatus according to claim 1, wherein thecontinuously adjustable controller has a click-stop and furthercomprising a click-stop releasing electromagnet, to release saidclick-stop from the controller.
 5. Apparatus according to claim 1,wherein the brake means comprises a braking element of permanentmagnetic material resiliently urged into engagement with the centralportion of the armature, said armature having a plurality of coilsdisposed thereon, wherein when electric current is passed in oppositedirections through said coils a magnetic pole is produced at the centralportion of the armature to repulse said braking element to release saidelement from the armature and when electric current is passed in thesame direction through said coils no magnetic pole is produced at thecentral portion of the armature, said braking element being held inengagement with said armature.
 6. Apparatus according to claim 1,wherein the brake means comprises a magnetizable braking elementresiliently urged into engagement with a braking plate fixed to thecentral portion of the armature, said armature having a plurality ofcoils disposed thereon, wherein when electric current is passed throughsaid coils in opposite directions a magnetic field is produced at thecentral portion of the armature to attract said braking element fromengagement with said braking plate and when electric current is passedthrough said coils in the same direction no magnetic field is producedat the central portion of the armature wherein said braking element isheld in engagement with said braking plate.
 7. Apparatus according toclaim 6, in which the armature has two adjacent pairs of opposed coilsdisposed thereon, wherein when electric current is passed in theopposite direction through every two adjacent coils and in the oppositedirections through every two opposed coils the magnetic field isproduced at the central portion of the armature and when electriccurrent is passed in the same direction through all of the coils nomagnetic field is produced at the central portion of the armature. 8.Apparatus according to claim 1 in which the armature has two adjacentpairs of opposed coils, every two adjacent coils having cores which areconnected together at their ends by a bridge member of magneticmaterial.
 9. Apparatus for memorizing and reproducing positions ofadjustment of a plurality of continuously adjustable controllers for anelectronic musical instrument, comprising: a plurality of yokes ofmagnetic material, each associated with one of said controllers, eachrotatably mounted on a pivot axis of the corresponding controller andmovable in correspondence with a position of adjustment of saidcorresponding controller; a plurality of armatures magneticallyengagable with a corresponding yoke rotatably mounted on each said pivotaxis and having armature coils disposed thereon, said armatures forminga plurality of series of armatures, each series including the armaturesengagable with a respective yoke; energizing means for selectivelyengaging one of said series of armatures; brake means engaging each ofsaid armatures for braking the rotation thereof; and releasing means forreleasing each of said brake means from engagement with said armatures.10. ApparatUs according to claim 9, comprising an electric currentsupplying source, a memorizing switch and a plurality of memorizing andreproducing switches, wherein the respective controllers include aplurality of armature coils and a plurality of brake releasing coils,the corresponding ones of said armature coils being connected to saidsource through the memorizing switch and one of the memorizing andreproducing switches and the corresponding ones of the break releasingswitches being connected to said source through one of the memorizingand reproducing switches.
 11. Apparatus according to claim 9, comprisingan electric current supplying source, memorizing switch means to reversethe direction of electric current supplied from said source, and aplurality of memorizing and reproducing switches, wherein the respectivecontrollers include a plurality of armature coils and a plurality ofbrake releasing coils, corresponding ones of the armature coils and thebrake releasing coils being connected to said source through thememorizing switch means and one of the memorizing and reproducingswitches.
 12. Apparatus according to claim 9, comprising an electriccurrent supplying source, a memorizing switch and a plurality ofmemorizing and reproducing switches, wherein the respective controllersinclude a plurality of pairs of armature coils and a plurality of brakereleasing coils, corresponding pairs of the armature coils andcorresponding ones of the brake releasing coils being connected to saidsource through the memorizing switch and one of the memorizing andreproducing switches, the junctions of the pairs of the armature coilsbeing connected to the source through one of the memorizing andreproducing switches.
 13. Apparatus for memorizing and reproducing aposition of an adjustable controller having operating lever means foradjusting said controller, comprising: a rotatable yoke made of magneticmaterial rotatable on a pivot axis, means mechanically connecting saidoperating lever with said rotatable yoke, an armature member rotatablymounted on said pivot axis in close proximity to said rotatable yoke,said armature member having a coil disposed thereon in magneticcooperation with said rotatable yoke, brake means for engaging saidarmature member for stopping said armature member, and means foractuating said brake means into engagement with and deactuating saidbrake means out of engagement with said armature member.